A conference to define AIDS in pediatric patients will be held in Marathon, Fl. on November 15 and 16, 1984. Approximately 40 physicians, scientists and federal workers directly engaged in AIDS or related work will attend. Working groups of 4-6 workers in each of three areas, clinical, pathological and immunological have met several weeks before the conference to prepare working documents. These documents will focus on inclusionary and exclusionary criteria for each area. Issued of broad agreement will be so identified and other areas will be reduced within reason to defined questions. The working documents will indicate pro and con positions on each unresolved question. Working documents will be sent to all conference participants at least one week prior to the conference. A fourth session at the conference will concern related topics where inadequate information or complex medical and/or social issues will be discussed briefly. Selected individuals will be asked to prepare an outline of an individual topic that will be part of the materials distributed to participants before the conference. The four major sessions of the conference will be conducted in a round table format. Each session will be moderated by a senior scientist not currently involved in AIDS research. The conference sessions will attempt to resolve those questions identified in the working documents. Immediately after each session the working group and moderator will reconvene and prepare an interim report from the working document. A copy of the interim report will be distributed to all conference participants prior to departure. No interim report of the related topics session is planned. Within two weeks of the conference a final report will be submitted. Final results from the conference will consist of either 3 separate publications or a composite report that encompasses clinical, pathological and immunological criteria for the diagnosis of AIDS in pediatric patients. Special emphasis will be devoted during the conference and in the final report to areas of future research in pediatric infectious diseases, immunology, etc. necessary for resolution and management of AIDS in this age group as well as the unique opportunities offered by this condition for understanding fundamental biologic processes.